This study is to determine the utility of a polymerase chain reaction using primers for candida species performed on serum collected on patients with invasive candidiasis or at risk for invasive candidiasis based on colonization. Systematic collection of specimens will allow determination of (1) is PCR more sensitive than blood culture in detecting invasive infection (2) will PCR allow rapid indication of infection and therefore earlier diagnosis and (2) how PCR results change with treatment and resolution of disease. grant=M01RR000840293 This study seeks to quantify Interleukin-8 (IL-8) levels in the sputum and plasma of patients hospitalized with cystic fibrosis. Il-8 levels will be obtained in these patients at the initiation of hospitalization and after one and two weeks of treatment with intravenous antibiotics and other therapeutic modalities. IL-8 levels will be correlated with clinical status as determined by NIH scoring, including pulmonary function testing and chest x-ray scoring.